Display devices and methods for forming display devices

ABSTRACT

A display device is provided. The display device includes a thin-film transistor substrate, a conductive pad disposed on the thin-film transistor substrate, and an adhesion film disposed on the conductive pad. The adhesion film includes a plurality of conductive particles. The display device also includes a light-emitting component disposed on the adhesion film. The light-emitting component includes a connection feature. The display device also includes a protection layer partially surrounding the light-emitting component. The connection feature of the light-emitting component has a lower portion not surrounded by the protection layer. The adhesion film has a thickness of T, one of the plurality of conductive particles has a diameter of d, the lower portion of the connection feature has a thickness of t, and 0&lt;t≤T−d.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority of provisional applications of, U.S.Patent Application No. 62/441,579 filed on Jan. 3, 2017, and U.S. PatentApplication No. 62/465,869 filed on Mar. 2, 2017, the entirety of whichare incorporated by reference herein.

BACKGROUND Technical Field

The disclosure relates to display devices, and in particular to displaydevices that include a light-emitting component surrounded by aprotection layer.

Description of the Related Art

As digital technology develops, display devices are becoming more widelyused in our society. For example, display devices have been applied inmodern information and communication devices such as televisions,notebooks, computers, mobile phones, and smartphones. In addition, eachgeneration of display devices has been developed to be thinner, lighter,smaller, and more fashionable than the previous generation.

Among the various types of display devices, light-emitting diode (LED)display devices are gaining in popularity, since LEDs have suchadvantages as high efficiency and a long life span.

However, existing LED display devices have not been satisfactory inevery respect.

BRIEF SUMMARY

Some embodiments of the disclosure provide a display device. The displaydevice includes a thin-film transistor substrate, a conductive paddisposed on the thin-film transistor substrate, and an adhesion filmdisposed on the conductive pad. The adhesion film includes a pluralityof conductive particles. The display device also includes alight-emitting component disposed on the adhesion film. Thelight-emitting component includes a connection feature. The displaydevice also includes a protection layer partially surrounding thelight-emitting component. The connection feature of the light-emittingcomponent has a lower portion not surrounded by the protection layer.The adhesion film has a thickness of T, one of the plurality ofconductive particles has a diameter of d, the lower portion of theconnection feature has a thickness of t, and 0<t≤T−d.

Some embodiments of the disclosure provide a method for forming adisplay device. The method includes providing a first temporarysubstrate with a first adhesion film thereon, providing a carrier with aplurality of light-emitting components thereon, attaching the pluralityof light-emitting components onto the first temporary substrate throughthe first adhesion film, removing the carrier from the plurality oflight-emitting components, providing a second temporary substrate with asecond adhesion film thereon, attaching the plurality of light-emittingcomponents onto the second temporary substrate through the secondadhesion film, removing the first adhesion film and the first temporarysubstrate from the plurality of light-emitting components, bonding theplurality of light-emitting components onto a thin-film transistorsubstrate, removing the second temporary substrate from the secondadhesion film, and removing the second adhesion film from the pluralityof light-emitting components.

Some embodiments of the disclosure provide a method for forming adisplay device. The method includes providing a first temporarysubstrate with a first plurality of light-emitting components thereon,and providing a first transfer substrate with a first plurality ofadhesive pads thereon. A pitch of the first plurality of adhesive padsis an integer multiple of a pitch of the first plurality oflight-emitting components on the first temporary substrate. The methodalso includes attaching a first group of the first plurality oflight-emitting components onto a first group of the first plurality ofadhesive pads on the first transfer substrate, removing the firsttemporary substrate while leaving the first group of the first pluralityof light-emitting components on the first transfer substrate, attachinga second group of the first plurality of light-emitting components ontoa second group of the first plurality of adhesive pads on the firsttransfer substrate, removing the first temporary substrate while leavingthe second group of the first plurality of light-emitting components onthe first transfer substrate, and bonding the first group and the secondgroup of the first plurality of light-emitting components onto athin-film transistor substrate.

Some embodiments of the disclosure provide a light-emitting structure.The light-emitting structure includes a light-emitting component and aprotection layer partially surrounding the light-emitting component. Theprotection layer includes an organic sub-layer and an inorganicsub-layer

A detailed description is given in the following embodiments withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure can be more fully understood from the following detaileddescription when read with the accompanying figures. It is worth notingthat in accordance with standard practice in the industry, variousfeatures are not drawn to scale. In fact, the dimensions of the variousfeatures may be arbitrarily increased or reduced for clarity ofdiscussion.

FIGS. 1A, 1B, 1C, 1D, 1E, 1F, 1G and 1H are cross-sectional views ofsome display devices according to some embodiments of the presentdisclosure.

FIGS. 2A, 2B and 2C are a series of cross-sectional views illustrating amethod for forming a display device according to some embodiments of thepresent disclosure.

FIGS. 3A, 3B, 3C, 3D, 3E, 3F, 3G, 3H, and 3I are a series ofcross-sectional views illustrating a method for forming a display deviceaccording to some embodiments of the present disclosure.

FIGS. 4A, 4B, 4C, 4D, 4E, 4F, 4G, 4H, and 4I are a series ofcross-sectional views illustrating a method for forming a display deviceaccording to some embodiments of the present disclosure.

FIGS. 5A, 5B, 5C, 5D, 5E, 5F, 5G, 5H, 5I, 5J, 5K, and 5L are a series ofcross-sectional views illustrating a method for forming a display deviceaccording to some embodiments of the present disclosure.

FIGS. 6A, 6B, 6C, and 6D are a series of cross-sectional viewsillustrating a method for forming a display device according to someembodiments of the present disclosure.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the subject matterprovided. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a first feature over or on a second feature in the description thatfollows may include embodiments in which the first and second featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the first and second features,such that the first and second features may not be in direct contact. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various embodiments. This repetition is for simplicityand clarity and does not in itself dictate a relationship between thevarious embodiments and/or configurations discussed.

Some embodiments are described below. Throughout the various views andillustrative embodiments, like reference numbers are used to designatelike features. It should be understood that additional operations can beprovided before, during, and after the method, and some of theoperations described can be replaced or eliminated for other embodimentsof the method.

Embodiment 1

Embodiment 1 provides a display device with a protection layersurrounding a light-emitting component. The protection layer may providethe display device with advantages, such as better reliability.

FIG. 1A illustrates a display device 10 of Embodiment 1. As shown inFIG. 1A, the display device 10 includes a substrate 100, one or moreconductive pads 102 disposed on the substrate 100, an adhesion film 104disposed on the conductive pad 102, one or more light-emittingcomponents 108 disposed on the adhesion film 104, and a protection layer110 partially surrounding the light-emitting component 108. The adhesionfilm 104 includes a plurality of conductive particles 106. Thelight-emitting component 108 includes a main portion 108 c (e.g., aportion made of semiconductor material, such as GaN) and a connectionfeature, such as 108 a and 108 b. In some embodiments, the thickness ofthe connection feature 108 a may be the same as the thickness of theconnection feature 108 b (as shown in FIG. 1A), but the thickness of theconnection feature 108 a may be different from the thickness of theconnection feature 108 b in other embodiments. The connection feature ofthe light-emitting component 108 has a lower portion not surrounded bythe protection layer 110. The adhesion film 104 has a thickness of T,one of the plurality of conductive particles 106 of the adhesion film104 has a diameter of d (e.g., the diameter of a conductive particle 106which is not disposed between the connection feature 108 a/108 b and theconductive pad 102), and the lower portion of the connection feature(i.e., 108 a and 108 b) has a thickness of t. In some embodiments, theconductive particle 106 which is disposed between the connection feature108 a/108 b and the conductive pad 102 is substantially oval (ellipse),while the conductive particle 106 which is not disposed between theconnection feature 108 a/108 b and the conductive pad 102 issubstantially round, as shown in FIG. 1A. In some embodiments, thediameter d of the round conductive particle 106 is greater than theminimum diameter of the oval conductive particle 106 and less than themaximum diameter of the oval conductive particle 106.

In some embodiments, the above parameters satisfy the equation 0<t≤T−d,so that the mechanical properties of the display device 10 can beimproved (e.g., the bonding between the substrate 100 and thelight-emitting component 108).

In some embodiments, the above parameters satisfy the equation d≤T≤3d,so that the mechanical properties of the display device 10 can beimproved (e.g., the bonding between the substrate 100 and thelight-emitting component 108).

For example, the diameter d of one of the plurality of conductiveparticles 106 can be 3.4 um, the thickness T of the adhesion film 104can be 4 um, and the thickness t of the lower portion of the connectionfeature can be 0.5 um.

The substrate 100 may include, for example, a thin-film transistorsubstrate. The thin-film transistor substrate may include one or morethin-film transistors, and the thin-film transistors may be arranged inan array.

The conductive pad 102 may be used to electrically connect thelight-emitting component 108 to the substrate 100. For example, theconductive pad 102 may include metal, metal alloy, other applicableconductive materials, or a combination thereof.

For example, the adhesion film 104 may include an anisotropic conductivefilm (ACF), which contains a plurality of conductive particles 106therein. In some embodiments, one of the plurality of conductiveparticles 106 has a diameter of d and may be made of metal, metal alloy,other applicable conductive materials, or a combination thereof. In someembodiments, as shown in FIG. 1A, the conductive particles 106 may havea core portion 106 a and a shell portion 106 b. For example, the coreportion 106 a may include a polymer, and the shell portion 106 b mayinclude metal or metal alloy coated on the core portion 106 a.

For example, the light-emitting component 108 may include alight-emitting diode (lateral or vertical), an organic light-emittingdiode, other applicable light-emitting components, or a combinationthereof. In the present embodiment, the light-emitting component 108 isa lateral light-emitting diode, and the connection feature of thelight-emitting component 108 includes a first bump (e.g., 108 a) and asecond bump (e.g., 108 b) which may be used as electrodes of thelight-emitting diode. As shown in FIG. 1A, the first bump (e.g., 108 a)and the second bump (e.g., 108 b) are spaced apart by a distance of G.In some embodiments, the diameter d of one of the plurality ofconductive particles 106 may be equal or less than half of G (i.e.,d≤G/2), and thus may be able to avoid the short circuit of theconnection feature 108 a and the connection feature 108 b. For example,the diameter d of one of the plurality of conductive particles 106 canbe 3.4 um, and the distance G between the first bump and the second bumpcan be 10 um.

In the present embodiment, as shown in FIG. 1A, the protection layer 110fills or partially fills the gap between the first bump (e.g., 108 a)and the second bump (e.g., 108 b), so that the reliability of thedisplay device 10 may be improved.

In some embodiments, the lower portion of the connection feature of thelight-emitting component 108 includes a first metal, the conductive pad102 includes a second metal (e.g., an upper portion of the conductivepad 102), and the plurality of conductive particles 106 includes a thirdmetal (e.g., the shell portion 106 b of the conductive particle 106). Insuch cases, a solid solution or an intermetallic compound of the firstmetal and the third metal may be formed (e.g., by a eutectic reaction)between the lower portion of the connection feature of thelight-emitting component 108 and the plurality of conductive particles106, to further improve the bonding between the light-emitting component108 and the plurality of conductive particles 106. Alternatively oradditionally, a solid solution or an intermetallic compound of thesecond metal and the third metal may be formed (e.g., by a eutecticreaction) between the conductive pad 102 and the plurality of conductiveparticles 106, and thus the bonding between the conductive pad 102 andthe plurality of conductive particles 106 may be improved.

In some embodiments, the third metal may include a metal or metal alloyapplicable for eutectic bonding (e.g., Sn, Ag, In, Cu, Au, Ni, Pd, Cr,Al, Ti, or a combination thereof), and the first metal and the secondmetal may respectively include a metal or metal alloy with a low meltingpoint (e.g., Sn, Ag, In, Cu, Au, Zn, Bi, Sb, or a combination thereof).In some other embodiments, the third metal may include a metal or metalalloy with a low melting point (e.g., Sn, Ag, In, Cu, Au, Zn, Bi, Sb, ora combination thereof), and the first metal and the second metal mayrespectively include Sn, Ag, In, Cu, Au, Zn, Bi, Sb, Ni, Pd, Cr, Al, Ti,or a combination thereof (i.e., metal or metal alloy applicable foreutectic bonding and/or metal or metal alloy with a low melting point).

In some embodiments, as shown in FIG. 1B, the protection layer 110 mayinclude an organic sub-layer 110 a, and an inorganic sub-layer 110 bsurrounding the organic sub-layer 110 a. In some embodiments, theinorganic sub-layer 110 b is the outermost layer of the protection layer110. For example, the organic sub-layer 110 a may include silicon-basedmaterial, acrylic-based material, other applicable organic materials, ora combination thereof. In some embodiments, the inorganic sub-layer 110b may include silicon oxide, silicon nitride, other applicable inorganicmaterials, or a combination thereof, and may be formed by lithographyprocess, ink jet, aerosol jet, other applicable processes, or acombination thereof. In some embodiments, the organic sub-layer 110 acan be used to support the light-emitting component 108 and prevent thelight-emitting component 108 from damage in a transferring process. Insome embodiments, the inorganic sub-layer 110 b may be used to changethe surface properties of the protection layer 110. For example, adistance A between a top surface of the light-emitting component 108 anda bottom surface of the organic sub-layer 110 a may be 1 μm to 100 μm.For example, a thickness P₁ of the organic sub-layer 110 a on thesidewall of the light-emitting component 108 may be 0.1 μm to 5 μm, anda thickness P₂ of the organic sub-layer 110 a adjacent to the connectionfeature (e.g., 108 a and 108 b) of the light-emitting component 108 maybe 0.1 μm to 10 μm. For example, a thickness P₃ of the inorganicsub-layer 110 b on the sidewall of the light-emitting component 108 maybe 0.1 μm to 5 μm, and a thickness P₄ of the inorganic sub-layer 110 badjacent to the connection feature (e.g., 108 a and 108 b) of thelight-emitting component 108 may be 0.1 μm to 10 μm. It should be notedthat the inorganic sub-layer 110 b may also be a multi-layered structureincluding two or more layers of inorganic material, such as SiNx/SiOx,SiOx/SiNx, SiN/Mo, or a combination thereof.

FIGS. 1C, 1D, 1E, 1F, 1G and 1H are some other embodiments of displaydevices with a protection layer including one or more organic sub-layersand inorganic sub-layers.

As shown in FIG. 1C, outermost sidewalls 110 a′ of the organic sub-layer110 a may be aligned with outermost sidewalls 108′ of the light-emittingcomponent 108.

As shown in FIG. 1D, outermost sidewalls 110 a′ of the organic sub-layer110 a may retract from the outermost sidewalls 108′ of thelight-emitting component 108.

As shown in FIG. 1E, outermost sidewalls 110 b′ of the inorganicsub-layer 110 b may also retract from the outermost sidewalls 108′ ofthe light-emitting component 108.

As shown in FIG. 1F, the protection layer 110 may further include aninnermost inorganic sub-layer 110 c, such that the organic sub-layer 110a is interposed between the outermost inorganic sub-layer 110 b and theinnermost inorganic sub-layer 110 c.

As shown in FIG. 1G, outermost sidewalls 110 c′ of the inorganicsub-layer 110 c may retract from the outermost sidewalls 108′ of thelight-emitting component 108.

In some embodiments the outermost sidewalls 110 a′ of the organicsub-layer 110 a, the outermost sidewalls 110 b′ of the inorganicsub-layer 110 b, and the outermost sidewalls 110 c′ of the inorganicsub-layer 110 c are substantially perpendicular to the top surface ofthe substrate 100 (as shown in FIGS. 1B-1G). In some embodiments, theangle between the outermost sidewalls 110 a′ of the organic sub-layer110 a and the top surface of the substrate 100 may be greater than zeroand less than π, and/or the angle between the outermost sidewalls 110 b′of the inorganic sub-layer 110 b and the top surface of the substrate100 may be greater than zero and less than π, and/or the angle betweenthe outermost sidewalls 110 c′ of the inorganic sub-layer 110 c and thetop surface of the substrate 100 may be greater than zero and less thanπ.

In some embodiments, at least one of the outermost sidewalls of thesub-layers of the protection layer 110 can taper inwardly in a directiontowards the substrate 100. For example, as shown in FIG. 1H, theoutermost sidewalls 110 a′ of the organic sub-layer 110 a taper inwardlyin a direction towards the substrate 100.

In some embodiments, the outermost sidewalls 110 a′ of the organicsub-layer 110 a, the outermost sidewalls 110 b′ of the inorganicsub-layer 110 b, and the outermost sidewalls 110 c′ of the inorganicsub-layer 110 c are substantially straight (as shown in FIGS. 1B-1G). Inother embodiments, at least one of the outermost sidewalls 110 a′ of theorganic sub-layer 110 a, the outermost sidewalls 110 b′ of the inorganicsub-layer 110 b, and the outermost sidewalls 110 c′ of the inorganicsub-layer 110 c may be curved.

Although not shown in the above figures, it should be noted that someadditional elements such as a cover plate or an optical film may beformed on the display devices of the above embodiments. For example, thecover plate may be made of glass, indium tin oxide, polyimide,polyethylene terephthalate, other applicable materials, or a combinationthereof. For example, the optical film may include a diffuser film, acondensing lens, other applicable optical films, or a combinationthereof.

It should be noted that the light-emitting structure which includes thelight-emitting component 108 and the protection layer 110 as illustratedin FIGS. 1A-1H are intended to be included within the scope of thepresent disclosure, and can be used in other embodiments of the presetdisclosure (e.g., Embodiments 2-6).

Embodiment 2

Embodiment 2 provides a method for forming display devices of the aboveembodiments.

First, as shown in FIG. 2A, the light-emitting component 108 including aconnection feature (e.g., 108 a and 108 b) is provided. Thelight-emitting component 108 is surrounded or partially surrounded bythe protection layer 110.

Then, as shown in FIG. 2A, the substrate 100 (e.g., a thin-filmtransistor substrate) with one or more conductive pads 102 formedthereon is provided. As shown in FIG. 2A, the adhesion film 104containing a plurality of conductive particles 106 is formed on thesubstrate 100 and the conductive pad 102. For example, the conductiveparticles 106 are randomly distributed in the adhesion film 104. Forexample, a spin-on coating or other applicable method can be used toform the adhesion film 104 on the substrate 100 and the conductive pad102.

Then, as shown in FIG. 2B, the light-emitting component 108 and thesubstrate 100 are bonded by a bonding process. For example, the bondingprocess may include a eutectic bonding process. As noted above, thelower portion of the connection feature (e.g., 108 a and 108 b) of thelight-emitting component 108 may include a first metal, the conductivepad 102 may include a second metal (e.g., an upper portion of theconductive pad 102), and the plurality of conductive particles 106 mayinclude a third metal (e.g., the shell portion 106 b of the conductiveparticle 106). Therefore, a solid solution or an intermetallic compoundof the first metal and the third metal may be formed between the lowerportion of the connection feature of the light-emitting component 108and the plurality of conductive particles 106 by the eutectic bondingprocess, and a solid solution or an intermetallic compound of the secondmetal and the third metal may be formed between the conductive pad 102and the plurality of conductive particles 106 by the eutectic bondingprocess.

Then, a curing process may be performed to cure the adhesion film 104.In some embodiments, the adhesion film 104 may be cured by anultraviolet light. In some other embodiments, the adhesion film 104 maybe thermally cured at a temperature higher than (e.g., 50° C. higherthan) the eutectic reaction temperature of the first metal and the thirdmetal and/or higher than (e.g., 50° C. higher than) the eutecticreaction temperature of the second metal and the third metal. Since theadhesion film 104 may be cured by an ultraviolet light or may be curedat a temperature higher than the eutectic reaction temperature of theeutectic bonding process, the adhesion film 104 remains uncured afterbeing subject to the bonding process (e.g., eutectic bonding process).Therefore, if the light-emitting component 108 is abnormal after thebonding process, it still can be removed or replaced with anotherlight-emitting component.

In some embodiments, as shown in FIG. 2C, a plurality of light-emittingcomponents can be bonded to the substrate 100 using the above method.For example, after the step of bonding the light-emitting component 108to the substrate 100, and before the step of curing the adhesion film104, a light-emitting component 208 surrounded by a protection layer 210and a light-emitting component 208′ surrounded by a protection layer210′ may be also bonded to the substrate 100. The light-emittingcomponent 108, the light-emitting component 208, and the light-emittingcomponent 208′ may be light-emitting diodes of different colors. Forexample, the light-emitting component 108 may be a blue light-emittingdiode, the light-emitting component 208 may be a green light-emittingdiode, and the light-emitting component 208′ may be a red light-emittingdiode.

In the present embodiment, the adhesion film 104 is formed on thesubstrate 100 before the bonding process. However, in some otherembodiments, the adhesion film 104 can be formed on the connectionfeature of the light-emitting component (e.g., light-emitting component108, 208, or 208′) before the bonding process.

Although not shown in the above figures, it should be noted that someadditional elements such as a cover plate or an optical film may also beformed on the substrate 100 to protect the display device or improve itsperformance.

Embodiment 3

Embodiment 3 provides a method for forming a display device bytransferring a plurality of light-emitting components to a substrate(e.g., thin-film transistor substrate).

First, as shown in FIG. 3A, a first temporary substrate 300 with a firstadhesion film 302 thereon is provided. For example, the first temporarysubstrate 300 may be made of glass, polyimide, polyethyleneterephthalate, other applicable materials, or a combination thereof. Forexample, the first adhesion film 302 may include a UV-light debondableadhesion film, a heat debondable adhesion film, other applicableadhesion films, or a combination thereof. In some embodiments, the firstadhesion film 302 may be a glue, a tape, or a combination thereof. Forexample, a spin-on coating or other applicable methods can be used toform the first adhesion film 302 on the first temporary substrate 300.In some embodiments, the first adhesion film 302 may be a patternedadhesion film formed by a lithography process, ink jet, aerosol jet,other applicable processes, or a combination thereof.

Still referring to FIG. 3A, a carrier 304 with a plurality oflight-emitting components 306 formed thereon is provided. For example,the carrier 304 may include a sapphire substrate, a silicon substrate, asilicon carbide substrate, other applicable carriers, or a combinationthereof. In some embodiments, the light-emitting components 306 mayinclude a light-emitting diode (lateral or vertical), an organiclight-emitting diode, other applicable light-emitting components, or acombination thereof. In the present embodiment, the light-emittingcomponent 306 is a light-emitting diode including a connection feature306 a (e.g., a bump or electrode of the light-emitting diode). In someembodiments, at least one of the light-emitting components 306 on thecarrier is partially surrounded by a protection layer (e.g., theprotection layer 110 shown in FIGS. 1B-1H).

Then, as shown in FIG. 3B, the plurality of light-emitting components306 are attached onto the first temporary substrate 300 through thefirst adhesion film 302. As shown in FIG. 3B, the connection feature 306a of the light-emitting component 306 extends into an upper portion ofthe first adhesion film 302.

Then, as shown in FIG. 3C, the carrier 304 is removed from the pluralityof light-emitting components 306. For example, the carrier 304 can beremoved by a laser lift-off process, a mechanical peeling, otherapplicable processes, or a combination thereof. For example, the lasersource of the laser lift-off process may include an excimer laser, apico laser, a femto laser, other applicable laser sources, or acombination thereof.

Then, as shown in FIG. 3D, a second temporary substrate 308 with alight-responsive layer 310 thereon is provided. For example, the secondtemporary substrate 308 may be made of glass, polyimide, polyethyleneterephthalate, other applicable materials, or a combination thereof. Forexample, the light-responsive layer 310 may include glue, and particlesdisposed in the glue. In some embodiments, the particles of thelight-responsive layer 310 can be expanded by a heating process (e.g., alaser heating process). For example, the light-responsive layer 310 maybe formed on the second temporary substrate 308 by a spin-on coatingprocess, other applicable processes, or a combination thereof.

Still referring to FIG. 3D, a second adhesion film 312 is formed on thelight-responsive layer 310 on the second temporary substrate 308. Forexample, the second adhesion film 312 may include a UV-light debondableadhesion film, a heat debondable adhesion film, other applicableadhesion films, or a combination thereof. In some embodiments, thesecond adhesion film 312 may be a glue, a tape, or a combinationthereof. For example, a spin-on coating or other applicable methods canbe used to form the second adhesion film 312 on the light-responsivelayer 310 on the second temporary substrate 312. In some embodiments,the second adhesion film 312 may be a patterned adhesion film formed bya lithography process, ink jet, aerosol jet, other applicable processes,or a combination thereof. In some embodiments, the second adhesion film312 is a patterned adhesion film including a plurality of adhesive pads(e.g., glue dots), and a pitch of the plurality of adhesive pads (e.g.,the distance between the center lines of two adjacent adhesive pads) isan integer multiple of a pitch of the plurality of light-emittingcomponents 306 (e.g., the distance between the center lines of twoadjacent light-emitting components 306) on the first temporary substrate300. In some embodiments, the second adhesion film 312 may be directlyformed on the second temporary substrate 308 (i.e., without forming thelight-responsive layer 310 on the second temporary substrate 308),and/or the second adhesion film 312 may be a single-layered ormulti-layered structure.

In some embodiments, the first adhesion film 302 on the first temporarysubstrate 300 can be debonded by a UV-light of a first wavelength, andthe second adhesion film 312 on the second temporary substrate 308 canbe debonded by a UV-light of a second wavelength that is different fromthe first wavelength. In some other embodiments, one of the firstadhesion film 302 and the second adhesion film 312 is a UV-lightdebondable film, and the other one of the first adhesion film 302 andthe second adhesion film 312 is a heat debondable film.

Then, as shown in FIG. 3E, the plurality of light-emitting components306 are attached onto the second temporary substrate 308 through thesecond adhesion film 312, such that the first adhesion film 302 and thesecond adhesion film 312 are on opposite sides of the light-emittingcomponents 306.

Then, as shown in FIG. 3F, the first adhesion film 302 and the firsttemporary substrate 300 are removed from the plurality of light-emittingcomponents 306 by a removal process. For example, the removal processmay include heating the first adhesion film 302 or exposing the firstadhesion film 302 to a UV-light to debond the first adhesion film 302.In addition, a mechanical peeling may be performed after heating thefirst adhesion film 302 or exposing the first adhesion film 302 to theUV-light.

In some embodiments, the first adhesion film 302 can be debonded by theUV-light of the first wavelength, and the second adhesion film 312 canbe debonded by the UV-light of the second wavelength that is differentfrom the first wavelength. In such embodiments, the first adhesion film302 can be debonded by exposing the first adhesion film 302 to theUV-light of the first wavelength, while leaving the second adhesion film312 substantially undisturbed.

In some other embodiments, one of the first adhesion film 302 and thesecond adhesion film 312 is a UV-light debondable film, and the otherone of the first adhesion film and the second adhesion film is a heatdebondable film. In such embodiments, since the first adhesion film 302and the second adhesion film 312 can be debonded by differentmechanisms, the first adhesion film 302 can be debonded while leavingthe second adhesion film 312 substantially undisturbed.

Then, as shown in FIG. 3G, the plurality of light-emitting components306 are bonded onto a substrate 314 (e.g., thin-film transistorsubstrate). In some embodiments, the substrate 314 has one or moreconductive pads and an adhesion film (e.g., anisotropic conductive film)formed thereon (not shown), and the plurality of light-emittingcomponents 306 may be bonded to the substrate 314 through the adhesionfilm and the conductive pads by the eutectic bonding process discussedin the above embodiments. In some embodiments, a filler layer (notshown) may be formed on the substrate 314 before the plurality oflight-emitting components 306 are bonded onto the substrate 314, so thatthe gap between adjacent light-emitting components 306 can be filled bythe filler layer.

Then, as shown in FIG. 3H, the second temporary substrate 308, and thelight-responsive layer 310 are removed from the second adhesion film312. As noted above, in some embodiments, the light-responsive layer 310includes particles being able to expand due to a heating process (e.g.,a laser heating process), and the expanded particles may be advantageousfor removing the second temporary substrate 308 and the light-responsivelayer 310 from the second adhesion film 312. Therefore, the step ofremoving the second temporary substrate 308 and the light-responsivelayer 310 from the second adhesion film 312 may include using a laserheating process to heat the particles of the light-responsive layer 310in some embodiments. In some embodiments, a mechanical peeling may beperformed after the heating process. In some embodiments, the secondadhesion film 312 is directly formed on the second temporary substrate308 (i.e., without forming the light-responsive layer 310 on the secondtemporary substrate 308), and thus only the second temporary substrate308 are removed from the second adhesion film 312.

Then, as shown in FIG. 3I, the second adhesion film 312 is removed fromthe plurality of light-emitting components 306 by a removal process. Insome embodiments, the removal process may include heating the secondadhesion film 312 or exposing the second adhesion film 312 to a UV-light(e.g., a UV-light of the second wavelength) to debond the secondadhesion film 312. In addition, a mechanical peeling may be performedafter heating the second adhesion film 312 or exposing the secondadhesion film 312 to the UV-light. In some embodiments, since the secondadhesion film 312 is heated or exposed to the UV light after the secondtemporary substrate 308 is removed, the debonding of the second adhesionfilm 312 can be improved.

In some embodiments, the debonding of the second adhesion film 312 canbe selective (i.e., a portion of the second adhesion film 312 isselectively debonded and another portion of the second adhesion film 312is not debonded). For example, portions of the second adhesion film 312which correspond to abnormal light-emitting components are not debonded(e.g., not exposed to the UV-light or not heated), and portions of thesecond adhesion film 312 which correspond to applicable light-emittingcomponents are selectively debonded, such that the abnormallight-emitting components can be removed with the second adhesion film312 while leaving the applicable light-emitting components on thesubstrate 314 (e.g., thin-film transistor substrate).

In some embodiments, both the light-responsive layer 310 and the secondadhesion film 312 can be debonded by heat. For example, the process ofremoving the second adhesion film 312 can include heating the secondadhesion film 312 at a first temperature (e.g., the minimum temperatureto debond the second adhesion film 312), and the process of removing thelight-responsive layer 310 can include heating the light-responsivelayer 310 at a second temperature (e.g., the minimum temperature todebond the light-responsive layer 310) less than the first temperature,such that the second adhesion film 312 are not debonded in the step ofremoving the light-responsive layer 310.

In some embodiments, the second adhesion film 312 can be debonded by theUV-light of the second wavelength, and the light-responsive layer 310can be debonded by a UV-light of a third wavelength different from thesecond wavelength. In such embodiments, the light-responsive layer 310can be debonded by exposing the light-responsive layer 310 to theUV-light of the third wavelength, while leaving the second adhesion film312 substantially undisturbed.

In some embodiments, one of the light-responsive layer 310 and thesecond adhesion film 312 is a UV-light debondable film, and the otherone of the light-responsive layer 310 and the second adhesion film 312is a heat debondable film. In such embodiments, the light-responsivelayer 310 can be debonded by the UV-light or heat, while leaving thesecond adhesion film 312 substantially undisturbed.

Although not shown in the above figures, it should be noted that someadditional elements such as a cover plate or an optical film may also beformed on the substrate 314 to protect the display device or improve itsperformance.

Embodiment 4

Embodiment 4 also provides a method for forming a display device bytransferring a plurality of light-emitting components to a substrate(e.g., thin-film transistor substrate). One difference betweenEmbodiment 3 and Embodiment 4 is that the light-responsive layer ofEmbodiment 4 is formed on the light-emitting components on the carrier.

First, as shown in FIG. 4A, a first temporary substrate 400 with a firstadhesion film 402 thereon is provided. For example, the first temporarysubstrate 400 may be made of glass, polyimide, polyethyleneterephthalate, other applicable materials, or a combination thereof. Forexample, the first adhesion film 402 may include a UV-light debondableadhesion film, a heat debondable adhesion film, other applicableadhesion film, or a combination thereof. In some embodiments, the firstadhesion film 402 may be a glue, a tape, or a combination thereof. Forexample, a spin-on coating or other applicable methods can be used toform the first adhesion film 402 on the first temporary substrate 400.In some embodiments, the first adhesion film 402 may be a patternedadhesion film formed by a lithography process, ink jet, aerosol jet,other applicable processes, or a combination thereof.

Still referring to FIG. 4A, a carrier 404 with a plurality oflight-emitting components 406 formed thereon is provided. For example,the carrier 404 may include a sapphire substrate, a silicon substrate, asilicon carbide substrate, other applicable carrier, or a combinationthereof. In some embodiments, the light-emitting components 406 mayinclude a light-emitting diode (lateral or vertical), an organiclight-emitting diode, other applicable light-emitting components, or acombination thereof. In the present embodiment, the light-emittingcomponent 406 is a light-emitting diode including a connection feature406 a (e.g., a bump or electrode of the light-emitting diode).

As shown in FIG. 4A, a light-responsive layer 408 is formed on thecarrier 404 and the plurality of light-emitting components 406 by anapplicable process (e.g., a spin-on coating process). In someembodiments, the light-responsive layer 408 is conformally formed on thecarrier 404 and the plurality of light-emitting components 406, as shownin FIG. 4A. For example, the light-responsive layer 408 may includeglue, and particles disposed in the glue. In some embodiments, theparticles of the light-responsive layer 408 can be expanded by a heatingprocess (e.g., a laser heating process).

Then, as shown in FIG. 4B, the plurality of light-emitting components406 are attached onto the first temporary substrate 400 through thefirst adhesion film 402. As shown in FIG. 4B, the connection feature 406a of the light-emitting component 406 extends into an upper portion ofthe first adhesion film 402.

Then, as shown in FIG. 4C, the carrier 404 is removed from the pluralityof light-emitting components 406. For example, the carrier 404 can beremoved by a laser lift-off process, a mechanical peeling, otherapplicable processes, or a combination thereof. For example, the lasersource of the laser lift-off process may include an excimer laser, apico laser, a femto laser, other applicable laser sources, or acombination thereof.

Then, as shown in FIG. 4D, a second temporary substrate 410 with asecond adhesion film 412 thereon is provided. For example, the secondtemporary substrate 410 may be made of glass, polyimide, polyethyleneterephthalate, other applicable materials, or a combination thereof. Forexample, the second adhesion film 412 may include a UV-light debondableadhesion film, a heat debondable adhesion film, other applicableadhesion films, or a combination thereof. In some embodiments, thesecond adhesion film 412 may be a glue, a tape, or a combinationthereof. For example, a spin-on coating or other applicable methods canbe used to form the second adhesion film 412 on the second temporarysubstrate 410. In some embodiments, the second adhesion film 412 may bea patterned adhesion film formed by a lithography process, ink jet,aerosol jet, other applicable processes, or a combination thereof.

Then, as shown in FIG. 4E, the plurality of light-emitting components406 are attached onto the second temporary substrate 410 through thesecond adhesion film 412, such that the first adhesion film 402 and thesecond adhesion film 412 are on opposite sides of the light-emittingcomponents 406.

Then, as shown in FIG. 4F, the first adhesion film 402 and the firsttemporary substrate 400 are removed from the plurality of light-emittingcomponents 406 by a removal process. As noted above, in someembodiments, the light-responsive layer 408 includes particles beingable to expand due to a heating process (e.g., a laser heating process),and the expanded particles may be advantageous for removing the firstadhesion film 402 and the first temporary substrate 400 from theplurality of light-emitting components 406. Therefore, the step ofremoving the first adhesion film 402 and the first temporary substrate400 from the plurality of light-emitting components 406 may includeusing a laser heating process to heat the particles of thelight-responsive layer 408 in some embodiments. In some embodiments, amechanical peeling may be performed after the heating process.

Then, as shown in FIG. 4G, the light-responsive layer 408 is removedfrom the plurality of light-emitting components 406. For example, thelight-responsive layer 408 can be removed with an organic solution(e.g., Acetone, alcohol, or methyl), an inorganic solution (e.g.,Silicone Oil), or a combination thereof.

Then, as shown in FIG. 4H, the plurality of light-emitting components406 are bonded onto a substrate 414 (e.g., thin-film transistorsubstrate). In some embodiments, the substrate 414 has one or moreconductive pads and an adhesion film (e.g., anisotropic conductive film)formed thereon (not shown), and the plurality of light-emittingcomponents 406 may be bonded to the substrate 414 through the adhesionfilm and the conductive pads by the eutectic bonding process discussedin the above embodiments. In some embodiments, a filler layer (notshown) may be formed on the substrate 414 before the plurality oflight-emitting components 406 are bonded onto the substrate 414, so thatthe gap between adjacent light-emitting components 406 can be filled bythe filler layer.

Then, as shown in FIG. 4I, the second adhesion film 412 and the secondtemporary substrate 410 are removed from the plurality of light-emittingcomponents 406 by a removal process. For example, the removal processmay include heating the second adhesion film 412 or exposing the secondadhesion film 412 to a UV-light to debond the second adhesion film 412.In addition, a mechanical peeling may be performed after heating thesecond adhesion film 412 or exposing the second adhesion film 412 to theUV-light.

Although not shown in the above figures, it should be noted that someadditional elements such as a cover plate or an optical film may also beformed on the substrate 414 to protect the display device or improve itsperformance.

It should be noted that, in some embodiments, the light-responsive layer408 may be replaced with a release film. For example, the release filmmay contain halogens. In some embodiments, a surface treatment may beperformed on the plurality of light-emitting components 406 beforeforming the release film on the plurality of light-emitting components406. In some embodiments, hydroxyl groups are formed on the surface ofthe light-emitting component 406 by the surface treatment.

Embodiment 5

Embodiment 5 provides a method for forming a display device bytransferring a plurality of light-emitting components to a substrate(e.g., thin-film transistor substrate).

First, as shown in FIG. 5A, a first carrier 500 with a first pluralityof light-emitting components formed thereon is provided. The firstplurality of light-emitting components includes a first group oflight-emitting components (i.e., 502) and a second group oflight-emitting components (i.e., 504). In some embodiments, the firstgroup of light-emitting components (i.e., 502) and the second group oflight-emitting components (i.e., 504) may be alternatively disposed. Forexample, the first carrier 500 may include a sapphire substrate, asilicon substrate, a silicon carbide substrate, other applicablecarrier, or a combination thereof. In some embodiments, thelight-emitting components 502 and 504 may include a light-emitting diode(lateral or vertical), an organic light-emitting diode, other applicablelight-emitting components, or a combination thereof. In the presentembodiment, the light-emitting components 502 and 504 are light-emittingdiodes including connection features 502 a and 504 a (e.g., a bump orelectrode of the light-emitting diode). In some embodiments, at leastone of the first plurality of light-emitting components on the firstcarrier 500 is partially surrounded by a protection layer (e.g., theprotection layer 110 shown in FIGS. 1B-1H).

Then, as shown in FIG. 5B, the first plurality of light-emittingcomponents 502 and 504 are attached onto a first temporary substrate 506through a first adhesion film 508. For example, the first temporarysubstrate 506 may be made of glass, polyimide, polyethyleneterephthalate, other applicable materials, or a combination thereof. Forexample, the first adhesion film 508 may include a UV-light debondableadhesion film, a heat debondable adhesion film, other applicableadhesion film, or a combination thereof. In some embodiments, the firstadhesion film 508 may be a glue, a tape, or a combination thereof. Forexample, a spin-on coating or other applicable method can be used toform the first adhesion film 508 on the first temporary substrate 506before the first plurality of light-emitting components 502 and 504 areattached onto the first temporary substrate 506.

Then, as shown in FIG. 5C, the first carrier 500 is removed from thefirst plurality of light-emitting components 502 and 504. For example,the first carrier 500 can be removed by a laser lift-off process, amechanical peeling, other applicable processes, or a combinationthereof. For example, the laser source of the laser lift-off process mayinclude an excimer laser, a pico laser, a femto laser, other applicablelaser sources, or a combination thereof. In some embodiments, at leastone of the first plurality of light-emitting components on the firsttemporary substrate 506 is partially surrounded by a protection layer(e.g., the protection layer 110 shown in FIGS. 1B-1H).

As shown in FIG. 5C, the first plurality of light-emitting components502 and 504 are disposed on the first temporary substrate 506 at a pitchof Q₁ (e.g., the distance between the center lines of two adjacentlight-emitting components of the first plurality of light-emittingcomponents). In some embodiments, the pitch Q₁ may be 2 to 500 μm, whosevalue depends on the size of LED chips.

Then, as shown in FIG. 5D, a first transfer substrate 510 with a firstplurality of adhesive pads (e.g., glue dots) thereon is provided. Thefirst plurality of adhesive pads includes a first group of adhesive pads(i.e., 512) corresponding to the first group of the first plurality oflight-emitting components (i.e., 502) and a second group of adhesivepads (i.e., 514) corresponding to the second group of the firstplurality of light-emitting components (i.e., 504). As shown in FIG. 5D,the first plurality of adhesive pads are disposed on the first transfersubstrate 510 at a pitch of Q₂ (e.g., the distance between the centerlines of two adjacent adhesive pads of the first plurality of adhesivepads). In some embodiments, the pitch Q₂ of the first plurality ofadhesive pads is an integer multiple of the pitch Q₁ of the firstplurality of light-emitting components (e.g., Q₂ is substantially equalto twice Q₁ in the present embodiment). For example, the first pluralityof adhesive pads may include a thermal plastic material, otherapplicable material, or a combination thereof. In some embodiments, thefirst plurality of adhesive pads can be formed by lithography process,ink jet, aerosol jet, other applicable processes, or a combinationthereof. In some embodiments, the material of the first plurality ofadhesive pads can include heat debondable materials and/or UV-lightdebondable materials.

Then, as shown in FIG. 5E, the first group of the first plurality oflight-emitting components (i.e., 502) are attached onto the first groupof the first plurality of adhesive pads (i.e., 512) on the firsttransfer substrate 510 by an attachment process. In some embodiments,the attachment process compresses the first group of the first pluralityof adhesive pads (i.e., 512), so that a thickness of the first group ofthe first plurality of adhesive pads (i.e., 512) is less than athickness of the second group of the first plurality of adhesive pads(i.e., 514) after the attachment process (as shown in FIG. 5E).

In some embodiments, a heating process or another applicable process maybe performed on the first group of the first plurality of adhesive pads(i.e., 512) before the attachment process, which may be advantageous tothe attachment process by increasing the plasticity of the first groupof the first plurality of adhesive pads (i.e., 512).

In some embodiments, since the pitch Q₂ of the first plurality ofadhesive pads is an integer multiple of the pitch Q₁ of the firstplurality of light-emitting components, the attachment process canselectively attach the first group of the first plurality oflight-emitting components (i.e., 502) onto the first transfer substrate510, while leaving the second group of the first plurality oflight-emitting components (i.e., 504) remaining on the first temporarysubstrate 506.

Then, as shown in FIG. 5F, the first temporary substrate 506, the firstadhesion film 508, and the second group of the first plurality oflight-emitting components (i.e., 504) are removed by a removal process,and the first group of the first plurality of light-emitting components(i.e., 502) are left on the first transfer substrate 510. In someembodiments, the first adhesion film 508 may be heated or exposed to aUV-light before the removal process, which may be advantageous to theremoval process by reducing the bonding force between the adhesion film508 and the first group of the first plurality of light-emittingcomponents (i.e., 502).

Then, as shown in FIG. 5G, the second group of the first plurality oflight-emitting components (i.e., 504) are attached onto the second groupof the first plurality of adhesive pads (i.e., 514) on the firsttransfer substrate 510 by an attachment process similar to the aboveattachment process for the first group of the first plurality oflight-emitting components (i.e., 502).

Then, as shown in FIG. 5H, the first temporary substrate 506 and thefirst adhesion film 508 are removed by a removal process, and the secondgroup of the first plurality of light-emitting components (i.e., 504) isleft on the first transfer substrate 510. In some embodiments, the firstadhesion film 508 may be heated or exposed to a UV-light before theremoval process, which may be advantageous to the attachment process byreducing the bonding force between the adhesion film 508 and the secondgroup of the first plurality of light-emitting components (i.e., 504).

Then, as shown in FIG. 5I, the first plurality of light-emittingcomponents (i.e., 502 and 504) are bonded onto a substrate 516 (e.g.,thin-film transistor substrate). In some embodiments, the substrate 516has one or more conductive pads and an adhesion film (e.g., anisotropicconductive film) formed thereon (not shown), and the first plurality oflight-emitting components may be bonded to the substrate 516 through theadhesion film and the conductive pads by the eutectic bonding processdiscussed in the above embodiments.

Then, as shown in FIG. 5J, the first transfer substrate 510 and thefirst plurality of adhesive pads (i.e., 512 and 514) are removed fromthe first plurality of light-emitting components (i.e., 502 and 504) bya removal process. For example, the removal process may include heatingthe first plurality of adhesive pads, exposing the first plurality ofadhesive pads to a UV-light, a laser lift off process, anotherapplicable process, or a combination thereof.

Although not shown in the above figures, it should be noted that someadditional elements such as a cover plate or an optical film may also beformed on the substrate 516 to protect the display device or improve itsperformance.

In some embodiments, a filler layer 518 may be formed on the substrate516 before the first plurality of light-emitting components (i.e., 502and 504) are bonded onto the substrate 516, so that the gap betweenadjacent light-emitting components can be filled by the filler layer (asshown in FIG. 5K). In some embodiments, a curing process may beperformed to cure the filler layer 518 after the first plurality oflight-emitting components (i.e., 502 and 504) are bonded onto thesubstrate 516. For example, the filler layer 518 may include glass,polyimide, flux, micro/nano particles, other applicable materials, or acombination thereof.

In some embodiments, the first transfer substrate 510 may not be removedafter the first plurality of light-emitting components (i.e., 502 and504) are bonded onto the substrate 516 (as shown in FIG. 5L). In suchembodiments, the first transfer substrate 510 may provide the displaydevice with some advantageous functions (e.g., mechanical protection oroptical conversion).

In some embodiments, the first plurality of adhesive pads (i.e., 512 and514) are formed by ink jet or aerosol jet after performing a testingprocess to test the quality of the first plurality of light-emittingcomponents (i.e., 502 and 504), and thus the pattern of the firstplurality of adhesive pads can be adjusted according to the test resultsto avoid the abnormal light-emitting components being transferred to thefirst transfer substrate 510. In some embodiments, the first pluralityof adhesive pads (i.e., 512 and 514) are formed by ink jet or aerosoljet before or after performing a testing process to test the quality ofthe first plurality of light-emitting components (i.e., 502 and 504),and some of the first plurality of adhesive pads corresponding to thelight-emitting components having abnormal quality (e.g., according tothe test results) may be removed by a removal process (e.g., a laserprocess) before the attachment process to avoid the abnormallight-emitting components being transferred to the first transfersubstrate 510.

Embodiment 6

Embodiment 6 provides a method for forming a display device. Onedifference between Embodiment 5 and Embodiment 6 is that two or moretransfer substrates are used in Embodiment 6.

First, as shown in FIG. 6A, a first transfer substrate 600 with a firstplurality of light-emitting components 604 formed thereon is provided.The first plurality of light-emitting components 604 are attached ontothe first transfer substrate 600 through a first plurality of adhesivepads 602. The first plurality of adhesive pads 602 have a pitch of M₁,which may be substantially equal to a pitch of the first plurality oflight-emitting components 604 on the first transfer substrate 600.

Still referring to FIG. 6A, a second transfer substrate 606 with asecond plurality of light-emitting components 610 formed thereon is alsoprovided. The second plurality of light-emitting components 610 areattached onto the second transfer substrate 606 through a secondplurality of adhesive pads 608. The second plurality of adhesive pads608 have a pitch of M₂, which may be substantially equal to a pitch ofthe second plurality of light-emitting components 608 on the secondtransfer substrate 606.

Still referring to FIG. 6A, a third transfer substrate 612 with a thirdplurality of light-emitting components 616 formed thereon is alsoprovided. The third plurality of light-emitting components 616 areattached onto the third transfer substrate 612 through a third pluralityof adhesive pads 614. The third plurality of adhesive pads 614 have apitch of M₃, which may be substantially equal to a pitch of the thirdplurality of light-emitting components 616 on the third transfersubstrate 612.

The transfer substrates, the adhesive pads and the light-emittingcomponents of the present embodiment may be the same as, or similar to,the above embodiments, and may be formed using the same or similarmethods as disclosed in the above embodiments.

In some embodiments, the pitch M₁ of the first plurality of adhesivepads 602, the pitch M₂ of the second plurality of adhesive pads 608, andthe pitch M₃ of the third plurality of adhesive pads 614 may besubstantially the same.

In some embodiments, the first plurality of light-emitting components604 includes light-emitting diodes of a first color, the secondplurality of light-emitting components 610 includes light-emittingdiodes of a second color, and the third plurality of light-emittingcomponents 616 includes light-emitting diodes of third color. In someembodiments, the first color, the second color, and the third color aredifferent from each other, and are selected from red, green, and blue.

Then, as shown in FIG. 6B, a bonding process is performed to bond thefirst plurality of light-emitting components 604 onto a substrate 618(e.g., thin-film transistor substrate). Then, the first transfersubstrate 600 and the first plurality of adhesive pads 602 are removedfrom the first plurality of light-emitting components 604.

Then, as shown in FIG. 6C, another bonding process is performed to bondthe second plurality of light-emitting components 610 onto the substrate618. Then, the second transfer substrate 606 and the second plurality ofadhesive pads 608 are removed from the second plurality oflight-emitting components 610.

Then, as shown in FIG. 6D, another bonding process is performed to bondthe third plurality of light-emitting components 616 onto the substrate618. Then, the third transfer substrate 612 and the third plurality ofadhesive pads 614 are removed from the third plurality of light-emittingcomponents 616.

In some embodiments, the pitch M₁ of the first plurality of adhesivepads 602, the pitch M₂ of the second plurality of adhesive pads 608, andthe pitch M₃ of the third plurality of adhesive pads 614 mayrespectively be an integer multiple of a pitch N₁ (as shown in FIG. 6D)of the light-emitting components transferred to the substrate 618 (i.e.,604, 610, and 616). For example, the pitch M₁ may is substantially threetimes the pitch N₁ in the present embodiment.

Although not shown in the above figures, it should be noted that someadditional elements such as a cover plate or an optical film may also beformed on the substrate 618 to protect the display device or improve itsperformance.

In some embodiments, a filler layer (not shown) may be formed on thesubstrate 618 before the light-emitting components (i.e., 604, 610, and616) are bonded onto the substrate 618, so that the gap between adjacentlight-emitting components can be filled by the filler layer. In someembodiments, a curing process may be performed to cure the filler layerafter the light-emitting components (i.e., 604, 610, and 616) are bondedonto the substrate 618. For example, the filler layer may include glass,polyimide, other applicable materials, or a combination thereof.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure. In addition, each claim can be an individualembodiment of the present disclosure, and the scope of the presentdisclosure includes the combinations of every claim and every embodimentof the present disclosure.

1. A display device, comprising: a thin-film transistor substrate; aconductive pad disposed on the thin-film transistor substrate; anadhesion film disposed on the conductive pad, the adhesion filmcomprising a plurality of conductive particles; a light-emittingcomponent disposed on the adhesion film, the light-emitting componentcomprising a connection feature; and a protection layer partiallysurrounding the light-emitting component, wherein the connection featurehas a lower portion not surrounded by the protection layer, and whereinthe adhesion film has a thickness of T, one of the plurality ofconductive particles has a diameter of d, the lower portion of theconnection feature has a thickness of t, and 0<t≤T−d.
 2. The displaydevice as claimed in claim 1, wherein the connection feature comprises afirst bump and a second bump, a distance G is between the first bump andthe second bump, and d≤G/2.
 3. The display device as claimed in claim 2,wherein the protection layer fills a gap between the first bump and thesecond bump.
 4. The display device as claimed in claim 1, whereind≤T≤3d.
 5. The display device as claimed in claim 1, wherein the lowerportion of the connection feature comprises a first metal, theconductive pad comprises a second metal, the plurality of conductiveparticles comprises a third metal, and wherein the first metal comprisesSn, Ag, In, Cu, Au, Zn, Bi, Sb, or a combination thereof, the secondmetal comprises Sn, Ag, In, Cu, Au, Zn, Bi, Sb, or a combinationthereof, and the third metal comprises Sn, Ag, In, Cu, Au, Ni, Pd, Cr,Al, Ti, or a combination thereof.
 6. The display device as claimed inclaim 1, wherein the lower portion of the connection feature comprises afirst metal, the conductive pad comprises a second metal, the pluralityof conductive particles comprises a third metal, and wherein the firstmetal comprises Sn, Ag, In, Cu, Au, Zn, Bi, Sb, Ni, Pd, Cr, Al, Ti, or acombination thereof, the second metal comprises Sn, Ag, In, Cu, Au, Zn,Bi, Sb, Ni, Pd, Cr, Al, Ti, or a combination thereof, and the thirdmetal comprises Sn, Ag, In, Cu, Au, Zn, Bi, Sb, or a combinationthereof.
 7. The display device as claimed in claim 1, wherein theprotection layer comprises an organic sub-layer and an inorganicsub-layer surrounding the organic sub-layer.
 8. The display device asclaimed in claim 7, wherein outermost sidewalls of the organic sub-layeris between outermost sidewalls of the light-emitting component.
 9. Thedisplay device as claimed in claim 8, wherein outermost sidewalls of theinorganic sub-layer is between outermost sidewalls of the light-emittingcomponent.
 10. The display device as claimed in claim 7, wherein theprotection layer further comprises another inorganic sub-layer, and theorganic sub-layer is interposed between the inorganic sub-layer and theanother inorganic sub-layer.
 11. A method for forming a display device,comprising: providing a first temporary substrate with a first adhesionfilm thereon; providing a carrier with a plurality of light-emittingcomponents thereon; attaching the plurality of light-emitting componentsonto the first temporary substrate through the first adhesion film;removing the carrier from the plurality of light-emitting components;providing a second temporary substrate with a second adhesion filmthereon; attaching the plurality of light-emitting components onto thesecond temporary substrate through the second adhesion film; removingthe first adhesion film and the first temporary substrate from theplurality of light-emitting components; bonding the plurality oflight-emitting components onto a thin-film transistor substrate;removing the second temporary substrate from the second adhesion film;and removing the second adhesion film from the plurality oflight-emitting components.
 12. The method as claimed in claim 11,wherein the step of removing the second adhesion film from the pluralityof light-emitting components comprises selectively debonding a portionof the second adhesion film.
 13. The method as claimed in claim 11,wherein the step of removing the first adhesion film and the firsttemporary substrate from the plurality of light-emitting componentscomprises exposing the first adhesion film to a light of a firstwavelength, and the step of removing the second adhesion film from theplurality of light-emitting components comprises exposing the secondadhesion film to another light of a second wavelength that is differentfrom the first wavelength.
 14. The method as claimed in claim 11,wherein one of the first adhesion film and the second adhesion film is aUV-light debondable film, and the other one of the first adhesion filmand the second adhesion film is a heat debondable film.
 15. The methodas claimed in claim 11, wherein at least one of the plurality oflight-emitting components on the carrier is partially surrounded by aprotection layer, and the protection layer comprises an organicsub-layer and an inorganic sub-layer.
 16. The method as claimed in claim11, further comprising: forming a filler layer on the thin-filmtransistor substrate before the step of bonding the plurality oflight-emitting components onto the thin-film transistor substrate. 17.The method as claimed in claim 11, wherein the second adhesion film is apatterned adhesion film.
 18. The method as claimed in claim 17, whereinthe second adhesion film comprises a plurality of adhesive pads, and apitch of the plurality of adhesive pads is an integer multiple of apitch of the plurality of light-emitting components on the firsttemporary substrate.
 19. A method for forming a display device,comprising: providing a first temporary substrate with a first pluralityof light-emitting components thereon; providing a first transfersubstrate with a first plurality of adhesive pads thereon, wherein apitch of the first plurality of adhesive pads is an integer multiple ofa pitch of the first plurality of light-emitting components on the firsttemporary substrate; attaching a first group of the first plurality oflight-emitting components onto a first group of the first plurality ofadhesive pads on the first transfer substrate; removing the firsttemporary substrate, while leaving the first group of the firstplurality of light-emitting components on the first transfer substrate;attaching a second group of the first plurality of light-emittingcomponents onto a second group of the first plurality of adhesive padson the first transfer substrate; removing the first temporary substrate,while leaving the second group of the first plurality of light-emittingcomponents on the first transfer substrate; and bonding the first groupand the second group of the first plurality of light-emitting componentsonto a thin-film transistor substrate.
 20. The method as claimed inclaim 19, further comprising: forming a filler layer on the thin-filmtransistor substrate before the step of bonding the first group and thesecond group of the first plurality of light-emitting components ontothe thin-film transistor substrate.
 21. The method as claimed in claim19, further comprising: providing a second transfer substrate with asecond plurality of light-emitting components thereon, wherein thesecond plurality of light-emitting components are attached onto thesecond transfer substrate through a second plurality of adhesive pads;and bonding the second plurality of light-emitting components onto thethin-film transistor substrate.
 22. The method as claimed in claim 21,wherein a pitch of the second plurality of adhesive pads is equal to thepitch of the first plurality of adhesive pads.
 23. The method as claimedin claim 21, wherein the first plurality of light-emitting componentscomprises a first plurality of light-emitting diodes of a first color,and the second plurality of light-emitting components comprises a secondplurality of light-emitting diodes of a second color different from thefirst color.
 24. The method as claimed in claim 19, wherein the firstplurality of adhesive pads comprise a UV-light debondable material or aheat debondable material.
 25. The method as claimed in claim 19, whereinat least one of the first plurality of light-emitting components on thefirst temporary substrate is partially surrounded by a protection layer,and the protection layer comprises an organic sub-layer and an inorganicsub-layer.
 26. A light-emitting structure, comprising: a light-emittingcomponent; and a protection layer partially surrounding thelight-emitting component, wherein the protection layer comprises anorganic sub-layer and an inorganic sub-layer.
 27. The light-emittingstructure as claimed in claim 26, wherein the inorganic sub-layer is theoutermost layer of the protection layer.
 28. The light-emittingstructure as claimed in claim 26, wherein outermost sidewalls of theorganic sub-layer is between outermost sidewalls of the light-emittingcomponent.
 29. The light-emitting structure as claimed in claim 28,wherein outermost sidewalls of the inorganic sub-layer is betweenoutermost sidewalls of the light-emitting component.
 30. Thelight-emitting structure as claimed in claim 26, wherein the protectionlayer further comprises another inorganic sub-layer, and the organicsub-layer is interposed between the inorganic sub-layer and the anotherinorganic sub-layer.